Linganisha mbinu

	Upendeleo wa Uchapishaji	Uhakiki wa Kisistimati
Nyanja	Takwimu za Utafiti	Uandishi wa Kitaaluma
Familia	Process / pipeline	Process / pipeline
Mwaka wa asili	1979	1992
Mwanzilishi	Robert Rosenthal	Cochrane Collaboration (1992)
Aina	Concept	Document Type
Chanzo asilia	Rosenthal, R. (1979). The file drawer problem and tolerance for null results. Psychological Bulletin, 86(3), 638–641.	Page, M. J., et al. (2021). The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. BMJ, 372, n71.
Majina mbadala	file drawer problem, selective reporting, outcome reporting bias, funnel plot asymmetry	systematic literature review, evidence synthesis, scoping review, mapping review
Zinazohusiana	4	3
Muhtasari	Publication bias occurs when the results of a study influence whether the study is published. Typically, studies with statistically significant or positive results are more likely to be published than studies with non-significant or negative results, even if both are scientifically valid. This bias distorts the published literature, making treatments appear more effective than they actually are. Rosenthal (1979) termed this the 'file drawer problem': research with null results sits in file drawers, unpublished, creating a biased sample of published evidence. Funnel plots and statistical tests (e.g., Egger test) can detect asymmetry suggesting publication bias; meta-analyses must account for this bias.	A systematic review is a structured, transparent synthesis of all available evidence addressing a specific research question. Unlike narrative reviews, systematic reviews employ comprehensive database searches, predefined selection criteria, quality assessment, and rigorous reporting (PRISMA guideline). The Cochrane Collaboration (founded 1992) established this methodology as the gold standard for evidence synthesis in healthcare and social sciences.